Figure 1
Iron homeostasis. Step 1 represents DMT1-mediated iron absorption into mature enterocytes. Step 2 indicates ferroportin-mediated movement of iron from enterocytes (and macrophages) into the circulation. Step 3 illustrates movement of iron from the circulation into hepatocytes and duodenal enterocytes fostered by the complex of Transferrin receptor 2 and the HFE protein. Step 4 indicates hepatocyte production and excretion of hepcidin into the circulation. Hepcidin downregulates activity of ferroportin, predominantly in duodenal enterocytes and macrophages (step 2).
